Course Content
Matter
OBJECTIVES By the end of this topic, the trainee should be able to 1.Define matter 2.Explain state of matter 3.Distinguish between physical and chemical changes 4.Explain the gas laws
0/4
Introduction
States of Matter
Physical and Chemical Properties and Changes
The Gas Laws
Atoms , Elements and Compounds
OBJECTIVES By the end of this topic , the trainee should be able to; 1.Define Elements, Compounds and Mixtures 2.Describe the structure of an atom 3.Describe how to determine the Atomic number ,Mass number and Isotopes
0/3
Introduction
Atomic Structure
Atomic Structure of Isotopes
The Periodic Table
OBECTIVES By the end of this topic, the trainee should be able to : 1.State the historical contribution on development of the periodic table 2.Explain the periodic trends of elements and their compounds 3.State the diagonal relationships of the periodic table
0/3
Introduction
Families of the Periodic Table
The Periodic Trends
The S-Block Element
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Explain the chemistry of group I and II elements 2.State the application of group I and two elements and their compounds
0/4
Introduction
Electronic Configuration of S-Block Elements
Physical Properties of S-Block Elements
Chemical Properties of S-Block Elements
Chemical Bonds
OBJECTIVES By the end of these topic, the trainee should be able to 1.Identify different types of bonds 2.Describe their properties
0/2
Introduction
Types and Properties of Chemical Bonds
Chemical Equilibrium
OBJECTIVES By the end of this topic , the trainee should be able to : 1.Define chemical equilibria 2.Explain types of equilibria 3.Determine equilibrium constant 4.Describe factors affecting chemical equilibrium
0/6
Introduction
Measuring Equilibrium Rates
Equilibrium Basics
Types of equilibria
Predicting The Direction of a Reaction
Factors Affecting equilibrium
Introduction To Organic Chemistry
By the end of this topic , the trainee should be able to : 1.Explain the aspects of organic chemistry 2.Describe hydrocarbons 3.Classify organic molecules explain chemical reactions of simple organic molecules 4.Explain the properties , synthesis and uses of simple organic molecules
0/10
Introduction
Functional Groups
Alkanes
Alkenes and Alkynes
Alkanols(Alcohols)
HaloAlkanes
Alkanals and Alkanones
Carboxylic Acids
Esters
Amines
Acids, Bases and Salts
OBJECTIVES By the end of this session , the trainee should be able to : 1.State properties of acids and bases 2.Differentiate between strong and weak acids 3.Explain types and properties of salts
0/2
Introduction
Properties Of Acids And Bases
PH Analysis
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define the term PH 2.Explain the basic theory of PH 3.State the relationship between PH and color change in indicators 4.Explain the term buffer solution 5.Describe the preparation of buffer solutions 6.State the application of buffer solutions
0/5
Introduction
Neutral, acidic and basic solutions
PH and Its Importance
Determination Of PH
Buffer Solutions
Sampling and Sample Preparation
OBJECTIVE By the end of this topic, the trainee should be able to : 1.Define the terms used in sample preparation 2.State the importance of sampling 3.Describe the techniques of sampling 4.Describe the procedure for sample pre-treatment 5.State sample storage methods
0/5
Introduction
Types of Samples and Sampling
Sample preparation
Sample Losses During Preparation
Sample Identification and Storage
Separation Techniques
OBJECTIVES By the end of this topic , the trainee should be able to : 1.Define separation, extraction and purification 2.Describe the separation , extraction and purification techniques 3.Explain the methods of determining purity of substances
0/2
Introduction
Separation Techniques
Heating and Cooling Techniques
OBJECTIVES To identify various techniques used for heating and cooling substances in the laboratory
Heating and Cooling Techniques
OBJECTIVES To identify various techniques used for heating and cooling substances in the laboratory
0/1
Heating and Cooling Techniques used in the lab
Distillation Techniques
By end of this topic, Trainee should be able to : 1. Define distilation 2. State and explain various distillation techniques 3. Outline Various distillation techniques 4. Outline the applications of Distillation techniques
0/3
Introduction
Types of Distillation Techniques 
Distillation and Reflux Condensers
Crystallization Techniques
OBJECTIVES By the end of the topic, the learner should be able to: 1.To define crystallization 2.To describe crystallization process 3.To carry out crystallization procedure
0/1
Crystallization Technique
Solvent Extraction Techniques
OBJECTIVES By the end of the topic, the learner should be able to 1.Define solvent extraction 2.Explain terms used in solvent extraction 3.Describe methods of solvent extraction 4.Describe selection of appropriate solvents for solvent extraction 5.Determine distribution ration 6.Outline factors actors influencing the extraction efficiency 7.Describe Soxhlet extraction
0/1
Introduction
Chromatography Techniques
OBJECTIVES By the end of this topic, the learner should be able to: 1.Define chromatography techniques 2.Explain terms used in chromatography techniques 3.Describe principles of chromatography techniques 4.Explain types of chromatography techniques 5.Carry out chromatography experiments 6.Determine RF factor 7.Outline electrophoresis
0/6
Introduction to Chromatography Techniques
Types of Chromatography Techniques
Thin Layer Chromatography
Column Chromatography
Retardation Factor (Rf)
Gas-Liquid Chromatography
Titrimetric Analysis
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define terms used in titrimetric analysis 2.Describe types of titrimetric analysis 3.Balance chemical reactions 4.Work out calculations involved in titrimetric analysis
0/6
Introduction
Requirements For Titrimetric Analysis
Titration procedure:
Molarity
Apparatus for titrimetric analysis
Classification Of Reactions In Titrimetrlc Analysis
Redox Titration
Redox Titration is a laboratory method of determining the concentration of a given analyte by causing a redox reaction between the titrant and the analyte. Redox titration is based on an oxidation-reduction reaction between the titrant and the analyte. It is one of the most common laboratory methods used to identify the concentration of unknown analytes. Redox reactions involve both oxidation and reduction. The key features of reduction and oxidation are discussed below.
0/5
Introduction
The oxidation number 
Balancing Redox Reactions
Examples Of Redox Titration
Standardization of Redox solutions
Complexiometric Titration
omplexometric Titration or chelatometry is a type of volumetric analysis wherein the colored complex is used to determine the endpoint of the titration. The method is particularly useful for determination of the exact number of a mixture of different metal ions, especially calcium and magnesium ions present in water in solution .
0/5
Introduction to Complexiometric Titration
EDTA titration
Types of EDTA titrations
EDTA titration experiment 
Mechanism of action of indicator:
Gravimetric Analysis
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define gravimetric analysis 2.Describe the principles of gravimetric analysis 3.Describe the steps involved in gravimetric analysis 4.Explain factors affecting gravimetric analysis 5.Describe the equipments and apparatus used in gravimetric analysis 6.Carry out gravimetric analysis
0/8
Introduction
Principles Of Gravimetric Analysis
Determination of Mass in gravimetric analysis
Factors Affecting Separation Of Metals And Compounds
Preparation of pure precipitates
Example of gravimetric Analysis
Gravimetric Calculations
Draft Lesson
Calorimetric Analysis
OBJECTIVES By the end of this topic, the trainee should be able to: 1.Define terms and units used in thermochemistry 2.Determine enthalpy changes in chemical reactions 3.Determine heat capacity and specific heat capacity 4.Compare calorific values of different materials 5.Determine different heat reactions 6.Apply law of conservation of energy and Hess law in thermochemical calculations
0/4
Introduction
Calorimetry
Heat Capacity
Enthalpy of Phase Transitions
Chemistry Techniques for Science Laboratory Technicians
About Lesson

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Types of equilibria

  1. Homogeneous Equilibria

 This occurs in  reactions in which all reactants and products are in the same liquid or gas phase.

A ↔ B

A can be in gas  or in liquid form   and B can be gas  or  in liquid form

  • Kc = [B]/[A]
  • Or
  • Kp =PB/PA

 Kc or Kp  is used  depending on whether A and B are in solution or in gas phase. The concepts of Kc isbased on molar concentrations of solution  whereas Kp, is  based on partial pressures of gaseous species.

In general Kc ≠ Kp unless the number of moles of gas does not change during the reaction.

If the equilibrium expression does not contain different powers of [A] or [B] in the numerator or denominator, the ration of [B]/[A] is the same as that of PB/PA. If there are different powers of [B] or A in the expression, then the ratio changes.

Heterogeneous Equilibria

This occurs in reactions in which   the reactants and the products are not in the same physical state or and in different phases.

If a solid or liquid is part of a chemical equilibrium, its “concentration” is taken as unity and may be eliminated from the equilibrium expression.

NH3(g) + HCl(g)  ↔  NH4Cl(s)

Keq  = [NH4Cl] / [NH3]·[HCl]

Since NH4Cl is a solid, its effective concentration in the reaction does not change as long as some solid is present. Since [NH4Cl] is constant, it can be eliminated from the right side of the equation and incorporated into the Keq constant, which them becomes

Keq  = 1/[NH3]·[HCl] if the molar concentrations of the gases will be expressed, or

Kp  = 1/PNH3·PHCl if the gas pressures will be expressed.

Example: How will [NH3] vary in the system as [HCl] increases or decreases?

Multiple Equilibria

The Keq values from two or more successive reactions are simply multiplied together if the reactions can be added together to make one net reaction.

  • For A → B  Keq = [A]/[B] and
  • For B → C, Keq = [B]/[C]

Adding the two equations together gives

                 A → C with Keq = [A]/[C]

The same Keq expression would have been obtained by multiplying together the two first K values. Applications include stepwise dissociation of polyprotic acids such as H3PO4

H3PO4↔ H2PO4-1  + H+1        K1= [H3PO4]/[ H2PO4-1] · [H+1]

H3PO4]/[ H2PO4-1] · [H+1]K2= etc

HPO4-2  ↔ PO4-3  + H+1      K3=   etc

K1

= [

The allover K = K1 · K2 · K3 for the equation

               H3PO4 → PO4-3  + 3H+1

 The Form of K and The Equilibrium Constant

The K for an equilibrium reaction is the reciprocal of the K for the reverse reaction. Therefore it is important to specify what reaction the K meant to represent.

For A ↔ B + C,

  •             Kf  = [B][C]
  •                        [A]
  • For B + C ↔ A,
  •                         Kr  = [A]
  •                               [B][C]

ThereforeKf xKr  = [A][B][C]/[A][B][C] = 1

Remember that the reactant and product concentrations in the Keq expression are raised to the power equal to their coefficients. What happens if the equation is written in more than one way?

H2(g) + I2(g) ↔ 2HI(g)

K1  = [H2][I2] /[HI]2

½H2(g) + ½I2(g)↔HI(g)

K2  = [H2] ½ [I2]½ /[HI]

Will the Keq values be different or the same for the two ways of writing the same equation? Consider both as representing the same system. Set [H2] = 0.020M, [I 2] = 0.030M and [HI] = 0.010M. Calculate both Keq values.

  • K1  = [H2][I2] /[HI]2  = (0.020M)(0.030M)/0.010M)2
  •                                      = 6.0
  • K2  = [H2]½ [I2]½ /[HI] = (0.020M)½ (0.030M)½ /(0.010M)1
  •                                       = 2.4 (or 6½)

                                              K1 = (K2)2

Both Keq values will give the same reactant and product concentrations when applied to the corresponding equations.

Relation Between Chemical Kinetics and Chemical Equilibrium

There is a direct relationship between the rate constant for the forward and reverse directions of a chemical reaction and the equilibrium constant for that reaction. That stands to reason because a large forward rate constant will lead to a larger K. A large backward rate constant will lead to a small K. for a first order chemical reaction,

A ↔ B, ratef  =kf [A] and Kf  = [B]/[A]

For the reverse reaction, B ↔ A, rater = kr[B] Kr  = [A]/[B]

By definition, at equilibrium the two rates, but not the kf and the kr, are the same. (Remember that the rates depend on the k values and on the A and B concentrations.)

If ratef  = rater, then kf [A] = kr[B]

kf /kr = [A]/[B] which is equal to the equilibrium constant, Kf. A large forward rate constant leads to a high rate of formation of B and a large value of Kf. Similarly, kr / kf = [B]/[A] = Kr.

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